In today""s environment many devices uses cryptographic techniques for ensuring the secure communication of data. One such device is a postage meter that prints an indication of value on a mailpiece and includes cryptographic data that is used to verify the authenticity of the indication of value. The cryptography used in each of these devices typically relies on the use of cryptographic keys that are changed on a periodic basis in order to ensure that the security of the cryptographic data being communicated is not compromised. However, when a device generates a new key(s) to replace a previously used key(s), the newly generated key(s) must be provided to all locations where the protected data is sent for decoding and reading.
The above-discussed transmission of the new key data has been accomplished in the past via the electronic communication of the new key data from one device to another. However, in many countries where postage meters are used there is no support of modem-based or other electronic communications to the postage meter. Nevertheless, it is still desirable to re-key the postage evidencing key and other keys used by the meter. Examples of such other keys are communication keys, postage value refill keys, and graphics keys. Therefore, what is needed is a simple and effective method to permit the transfer of newly generated keys from the postage meter to another device or location when the electronic communication of such keys is not possible.
A method for communicating a re-keying message from a postage meter to a registration authority includes the steps of determining at the postage meter that a current key needs to be replaced with a new key; generating in the postage meter the new key; creating in the postage meter the re-keying message, the re-keying message including at least a device identifier and the new key; using the postage meter for printing the re-keying message in a machine-readable form on a recording medium; and mailing the recording medium to the registration authority.